论文标题
3D离散元素模拟颗粒系统的线性接触模型
Linear-frictional contact model for 3D discrete element simulations of granular systems
论文作者
论文摘要
线性摩擦接触模型是颗粒材料离散元素（DEM）模拟的最常用的接触机制。带有摩擦滑块的线性弹簧用于在正常的方向上建模相互作用，并与接触表面进行切线。尽管该模型在二维上很简单，但其在3D面对某些微妙的挑战中实现，并且在单个时步中发生的粒子相互作用需要使用可靠的算法进行仔细的建模。本文详细介绍了一种3D算法，该算法解释了一个时间步长内切向力的方向的变化，在时间步长中从弹性到滑动行为的过渡，仅在时间步长的一部分中可能的接触滑动以及时间步长期间切向力的旋转和旋转。如果没有这些调整，则会以组件的增量刚度引入错误。没有第四个调整，所得的应力张量不仅不正确，而且不再是张量。该算法还计算了在弹性和耗散的时间步长期间的工作增量。
The linear-frictional contact model is the most commonly used contact mechanism for discrete element (DEM) simulations of granular materials. Linear springs with a frictional slider are used for modeling interactions in directions normal and tangential to the contact surface. Although the model is simple in two dimensions, its implementation in 3D faces certain subtle challenges, and the particle interactions that occur within a single time-step require careful modeling with a robust algorithm. The paper details a 3D algorithm that accounts for the changing direction of the tangential force within a time-step, the transition from elastic to slip behavior within a time-step, possible contact sliding during only part of a time-step, and twirling and rotation of the tangential force during a time-step. Without three of these adjustments, errors are introduced in the incremental stiffness of an assembly. Without the fourth adjustment, the resulting stress tensor is not only incorrect, it is no longer a tensor. The algorithm also computes the work increments during a time-step, both elastic and dissipative.
